1. Field of the Invention
The present invention relates in general to surgical devices and methods for treatment of a body, and more particularly to devices and methods for transferring electromagnetic radiation to the body along or through a flexible conduit such as a waveguide.
2. Information Disclosure Statement
Laser ablation is used in a wide range of medical applications for the purpose of vaporizing tissue in order to remove mass of unwanted tissue or an obstruction. Different types of laser ablation devices operating at specific laser wavelengths and powers are commonly used for this variety of applications. In general, for a laser to ablate tissues the power density or fluence must be high, consequently, high power laser sources are required for vaporizing tissue and finishing the procedures in a reasonable period of time. However, undesirable effects like the destruction of laser-irradiated tissue or damage to optical components also result from laser ablation. Hence, there is a need of methods and devices that effectively deliver high-power laser radiation to tissue in a safe, precise and reliable manner while preserving the optical components and protecting healthy tissue surrounding the treatment site.
In an attempt to overcome these drawbacks, US Patent Application Publication No. 2011/0160713, and International Publication No. WO 2011/037651 both by Neuberger disclosed an optical fiber set with an asymmetric distal end configuration, comprising a bent tip fiber with a fused sleeve and a rotatable connector. The main difference with this invention is that the clad, core and cap of the optical fiber set are bent and define the tissue-contacting surface. A disadvantage of this configuration is that the stability of the optical fiber is reduced and undergoes degradation because the fiber tip is close or in contact with tissue. Present invention overcomes this drawback and provides a simpler device easy to fabricate and with bigger tissue-contacting surface, reducing the treatment time while enhancing the ablation procedure.
A side-firing optical surgical fiber assembly is disclosed in International Publication No. WO 2012/112386 by Tumminelli. The side-firing assembly intends to overcome the laser-induced pitting caused by one or more damage mechanisms by hardening the outer surface of the capillary, specifically, by creating a relatively high compressive stress in the surface. This invention requires specific materials and parameters leading to a complex fabrication process. In contrast, the devices and methods of present invention are easy to manufacture, more stable and provide a range of predetermined orientations of the laser beam in order to obtain a device that can be easily and efficiently operated by the physician.
Due to the disadvantages and deficiencies of current waveguide devices used in high power medical applications, a need exists for a device that provides a stable, safe and robust alternative which significantly reduces the damage to the waveguide devices caused by back-reflection of laser radiation, water-vapor bubbles, or ablated material depositing on the tip. Furthermore, there remains a need for quicker and more efficient procedures, causing less stress on patients and requiring less time of the physician.